As telecommunications usage increases as a result of, for example, increased Internet usage, increased types of communications, population growth, telecommunications providers are required to provide greater voice- and data-carrying capacity. In order to reduce cost and the amount of time required to provide the increased capacity wavelength division multiplexing (WDM) and dense wavelength division multiplexing (DWDM) have been developed, which provide increased capacity without requiring new fiber optic cables.
WDM and DWDM technologies combine multiple optical signals into a single fiber by transporting each signal on a different optical wavelength or channel. Multiplexing and demultiplexing of optical channels is typically accomplished with thin film optical filters. However, multiple layers of film are required to multiplex and demultiplex multiple channels, which increases the cost and complexity of a component. Another disadvantage of multiple layers of thin film for filtering is that the thin films break down over time, especially when operating under high power conditions.
What is needed is an improved optical device for use with WDM and/or DWDM optical signals.